Wiring device



WIRING DEVICE Original Filed June 9, 1955 3 Sheets-Sheet 1 Fig. 2 36 4232 24 26 43 22 2o 6 1 3o 45 45 4 30 28 8 .I/ I LI 64 28 I I 94 34 45 9e94 66 1 3c 28 92% I 3% G74 28 *zsono 92 I I 98 34 5 93 66 I 30 I6 43 32so INVENTOR Robert D. Howells.

ATTORNEY May 1, 1962 R. D. HOWELLS 3,032,736

WIRING DEVICE Original Filed June 9, 1955 3 Sheets-Sheet 2 Y 9' if f l5| 3s 4s 21 Fig. 5. 5O 5 419 SI 4e 46- Q 46 I5 I4 34 22 22 a9 39 I P as3 4- 6' i; 62

y 1962 R. D. HOWELLS 3,032,736

WIRING DEVICE Original Filed June 9, 1955 3 Sheets-Sheet 3 FIGS Mk I I 1a no 29. no I7 62 States nite The present invention relates to a new andimproved grounding wiring device, and, more particularly, to a 3-wiregrounding convenience outlet. This application is a continuation of anapplication of R. D. Howells, entitled Wiring Device, Serial No.514,274, filed June 9, 1955, now abandoned, and assigned to the presentassignee.

As is well known, the electrical industry has standardized upon the sizeand location of various electrical components which are used in orderthat the components may be used interchangeably without regard to theirmanufacture. In the case of outlets, their design was originallypredicated on the use of a two-wire system,

jacent a slot or opening when an attachment cap is in-- serted orwithdrawn at an angle other than 90 degrees to the face of the outlet,because the design is such that considerable force can then be exertedagainst the ma terial of the casing of the outlet by engagement of thegrounding prong or blade of the attachment cap. Such force hasfrequently been of sufiicient magnitude as to break a part of thecasing. The device may thus be rendered useless.

Accordingly, one object, generally speaking, of my in-; vention is toprovide a new and improved grounding wir-j;

ing device.

A more specific object of my invention is to provide a new and improvedgrounding convenience outlet having a cover having a novel, formedground prong receiving opening.

Another more specific object of my invention is to provide a new andimproved grounding convenience outlet which has an elongated slot openat one end in the cover to receive the grounding prong of an insertedattachment cap.

Another object of my invention is to provide a new and improvedgrounding wiring device having an elongated grounding contact locatedwithin the device and a yoke member engageable with a free end of thegrounding contact to limit movement thereof when a grounding prong isinserted within the device.

Still another object of my invention is to provide a new and improvedgrounding wiring device having an elongated grounding contact supportedby the device which is located below a slot in the cover of the deviceand a yoke member which is engageable with a free end of the groundingcontact to limit movement of the contact when a grounding prong isinserted therein.

These and other objects of my invention will become more apparent uponconsideration of the following detailed description of wiring devicesconstructed in accordance with the principles of my invention when takenin conjunction with the attached drawings, in which:

FIG. 1 is a top plan view of a wiring device constructed in accordancewith the principles of my invention;

FIG. 2'is a top plan view of the body of the wiring One atenlt 3,032,735Patented May 1, 1962 ice . device, as shown in FIG. 1, with the coverthereof re moved so as to show the terminals and yoke located withrespect thereto;

FIG. 3 is a longitudinal cross-sectional view of the wiring device shownin FIG. 1 taken along the lines III-III of FIGS. 1 and 2;

used in the wiring device as shown in FIGS. 1 to 3;

FIG. 8 is a partial view of a yoke member which forms a part of thewiring device of FIG. 4.

, Referring to FIG. 2, it will be noted that a convenience outletconstructed in accordance with the principles of my invention comprisesan elongated cup-shaped body the structure as hereinafter described.

2, which may be formed from any suitable insulating material, and ispreferably formed from a molded phenolic insulating material which mayreadily be provided with Body 2 comprises an approximately rectangularbase 4 having upwardly extending formed opposed side wall portions 6which are joined together at one end of base 4 by an upwardly extendingend wall portion 8. Side walls 6 are also joined together by means ofanother end wall portion 10 extending upwardly from base 4 which islocated longitudinally inwardly of the other end of body 2 and which islongitudinally spaced from end Wall 8. As more fully describedhereinafter, end Wall 10 of body 2 is also provided with a pair oflaterally spaced projections 12 and 14 which extend longitudinallyoutwardly from the outer surface of end wall 10. In order to providesupport for a cover 40, hereinafter described, the

upper surfaces of projections 12 and 14 are in the same v plane astheupper edgestof side walls 6 and end wall 8.

Body 2 is also provided with an integral irregularly formed barrier 18which extends longitudinally between the end walls 8 and 1t! andcentrally between the side walls 6 so that the body 2 is divided intotwo identically formed longitudinally extending chambers 16. Each Ichamber 16 is formed to slidably receive an elongated may readily beformed as hereinafter described, such as 4 copper or an alloy thereofsuch as brass.

Each terminal 20 comprises a pair of generally square terminal portions22 which are longitudinally spaced from each other and extendlongitudinally outward in opposite directions from the center of theterminal 20. An upwardly and outwardly angularly extending tab 24 isformed integral with a portion of the adjacent upper edges of eachterminal portion 22 and extends across the space therebetween so as toelectrically connect terminal portion 22 together. If it is desired toelectrically isolate terminal portions 22 from each other, the tab 24need only be removed, and in order to facilitate such removal thejunction line between tab 24 and terminal portions 22 may be scored. Tofurther facilitate such removal, tab 24 is provided with alongitudinally extending slot 26 into which any suitable means such asthe blade of a screwdriver may be inserted so that the tab 24 may bebent around its scored junction. In order to provide prong engagingmeans at each end of the terminal 20, the lower portion of the oppositesides of terminal portions 22 is provided with an integral U-shaped endwhich is formed so that its bight portion is approximately parallel to,but laterally spaced from, the terminal portions 22 and is on theopposite side of the terminal portions 22 from which the tab 24 extends.The open end of each U-shaped end 110 of terminal 20 is approximately inthe same longitudinal plane as the terminal portions 22. Each arm andthe bight portion of each U-shaped end 110 are provided with an upwardlyextending blade 28, each of which is bent inwardly towards the middle ofthe U- shaped end 110 but being slightly spaced from each other so as toform a T-shaped opening therebetween. If desired, each blade 28 may beprovided with an integral angularly upwardly and outwardly extendingouter projection 30 for guiding the prongs of an inserted attachment capwithin the T-shaped opening. In order to provide external access fromthe body 2 to the terminal portions 22, each side wall 6 is providedwith a longitudinally elongated opening 32 which extends downwardly fromthe upper edge of side walls 6 to the upper surface of base 4 of body 2.

By such construction, a terminal 20 may be easily inserted in eachchamber 16 of body 2 by placing the lon gitudinally spaced U-shaped ends110 in opposite ends of a chamber 16 so that the terminal portions 22are located in a plane adjacent the inner surface of sidewalls 6 and sothat they extend longitudinally across opening 32. Each side of barrier18, is provided with a laterally outwardly extending intermediate wall34 which also extends upwardly from base 4. Each intermediate wall 34extends between the adjacent sides of terminal portions 22 of theterminal 20 adjacent thereto and has its upper edge located adjacent thelower edge of tab 24. Each terminal portion 22 is provided with anelongated openended upwardly extending slot of a size to receive theshank of a terminal screw 36 in order that electrical connections mayreadily be made thereto. In order to prevent adjacent portions of theterminal portions 22 from being forced inwardly of body 2 whenelectrical connections are made thereto, base 4 is provided with anupwardly extending ledge 39 which extends longitudinally outwardly fromeach intermediate wall 34 at each side thereof so that their outerlongitudinally extending edges engage the inner surface of the portionof each of the terminal portions 22 adjacent the intermediate walls 34.The upper edge of each terminal portion 22 is provided with an upwardlyextending projection 42 which is longitudinally spaced away from the tab24 and which is engageable with a portion of the cover 40, ashereinafter described to additionally support the terminal portions 22.It will also be noted that the shank of each of the terminal screws 36is provided with a floating rectangular clamping nut 43 so thatelectrical connections may readily be made to either side of theterminal portions 22 of terminal 20 in the well-known manner. In orderto permit internal wiring of the outlet, base 4 is provided with anopening 45 inwardly adjacent each terminal portion 22 at the side of theshank of terminal screw 36.

Referring to FIG. 5, body 2 is enclosed by means of an elongated cover40 which may be fabricated from any suitable insulating material, suchas a molded phenolic material which may be readily provided with thenecessary structure as hereinafter described. Cover 40 is formed so asto be cooperable with body 2 so that an over all unitary housing isobtained. Each side of cover 40 is provided with a pair of downwardlyextending projections 46 with the projections at each side beinglongitudinally spaced so as to extend into opposed sides of opening 32so that when cover 40 is placed on body 2 projections 46 are locatedbetween and in engagement w1th the opposite edges of opening 32 andcover 40 is definitely located longitudinally with respect to body 2.Although not shown, the undersurface of cover 40 is provided with aplurality of downwardly extending projections which are located so as tobe adjacent the inner surfaces of sidewalls 6 and end walls 8 and attheir junction point so that the cover 40 is both longitudinally andlaterally located with respect to body 2. Also, each projection 46 isprovided with a centrally upwardly extending recess 48 for closelyreceiving the upper end of the adjacent projection 42 so that theterminals 20 are additionally secured against deflection inwardly ofbody 2 when wiring connections are made thereto. As shown in FIG. 3, theundersurface of cover 46 is centrally provided with an extendinglongitudinally centrally located inner rib 47 which engages the uppersurface of barrier 18.

Cover 41 is also provided with a pair of longitudinally spacedapproximately circular projections 50 and 51 which extend upwardly froman upper surface 5 on cover 40 in each of which extend upwardly from anupper surface 5 on cover 40 in each of which are located a pair oflaterally spaced longitudinally elongated slots 52. Slots 52 areprovided (FIG. 1) in order that the prongs of an attachment cap, notshown, may be inserted in the longitudinally extending opening betweencontacts 28 to engage the contacts 28 at one end of each of theterminals 20. If desired, laterally spaced laterally extending slots(not shown) may be provided in cover 40 so that prongs 111 of one typeof attachment cap 120, shown in FIG. 6, may be inserted in the laterallyextending opening between contacts 28 to engage contacts 28. In order tofacilitate the insertion of such prongs 111, the outer surfaces ofprojection 50 are slightly dished inwardly and an integral divider 54 isprovided on each projection 50 which extends longitudinally between theslots 52. As is well known, an attachment cap which is used to engagethe contacts 28 at one end of each terminal 20 comprises a pair ofspaced contact engaging prongs 111, which are parallel with each other,and a grounding prong which is located centrally between the contactengaging prongs and offset to one side of the plane passing through thecenter of the contact engaging prongs 111. Such prong spacing and theirsize have been standardized by the electrical industry as well as thesize of the outlet box for receiving a convenience outlet. In order tocomply with such standards, it will be noted that a grounding prongreceiving opening 56 is provided in projection 50, which is locatedlongitudinally inwardly of the slots 52 in the projection 50 and asimilar purpose opening 58 for the projection 51 is locatedlongitudinally outwardly of the slots 52 of the projection 51 in orderthat projections 50 and 51 will be substantially identically formed. Asshown, opening 56 has a straight side extending laterally between thesides of cover 40, the ends of which are joined together by means of acurved segment so that a reversed D-shaped opening is formed.

Referring to FIGS. 1, 2 and 3, it will be noted that the assemblycomprising the cover 40 and base 2 with the terminals 20 therein isadapted to be supported in a standard outlet box by a generally U-shapedyoke 60 which may be made of any suitable material having sufficientstructural strength, such as sheet steel, and which may be formed asherein described. In order to locate yoke 60 with respect to body 2, theouter portion of base 4 of body 2 is provided with a centrallongitudinally extending slot 62, which has a lateral width to receivethe bight portion 76 of yoke 60 therein. One end of slot 62 is inalignment with an upwardly extending slot 64 in the outer surface of theend wall 8. Similarly, the outer ends of projections 12 and 14 are eachprovided with an openended laterally extending recess 66, the ends ofwhich are laterally spaced apart the same distance as the lateral widthof slot 62 and are in alignment with the other end of slot 62. By thisconstruction, body 2 may easily be placed upon the yoke 60 by merelypermitting spaced arms 68 of yoke 60 to enter the spaced recesses 66 andslot 64 and thereafter lowering the body 2 between the arms 68 until thebight portion 70 of yoke 69 enters slot 62. It will be noted that theentire assembly is adapted to be secured together by any suitable meansextending therethrough which, as shown, may comprise a bolt 73 extendingthrough aligned openings 72, 74, 76 in yoke 66, barrier 18 of housing 2anda portionof cover 40 between the projections 50 and 51, respectively.The upper end of bolt 78 is provided with a centrally located downwardlyextending threaded opening 82 in order that a standard face plate may besecured to the convenience outlet in the well-known manner. By providingopening 82, thin side walls 84 are formed at the upper end of bolt 78which may be forced outwardly in any suitable manner such as by beingspun over the upper surface of cover 49 to clamp the cover 49, body 2and yoke 60 between the turned side walls 34 of bolt 73 located inengagement with the outer surface of yoke 69. In order to obtain a flushsurface, it will be noted that the turned side walls 84 are located in acounterbore 101 at the upper end of opening 76 in cover 4t). It willalso be noted that each arm 68 of yoke 60 is provided at its upper edgewith a longitudinally outwardly extending tab having suitable openingstherein which are spaced a distance to comply with the elec tricalstandards so that the convenience outlet may be secured to the standardoutlet box in the well-known manner.

In order that grounding connections may be made at the projections 50and 51, a pair of identically formed U-shaped spaced contacts 80 and 81are secured to yoke 60 so as to be in alignment with the spaced openings56 and 58, respectively, in cover 40. As shown in FIG. 3, contacts 80and 81 each are provided with a pair of elongated longitudinally spacedupwardly extending contact arms 92 and 93. As shown, contact arm 92extends angularly toward the other contact arm 93 in order to obtain abetter spring action between the arms 92 and 93 of each contact.Accordingly, contacts 80 and 81 are fabricated from any suitableelectrical conducting material having sufficient resiliency so as tofunction as described, such as a copper alloy. Arms 92 and 93 of eachcontact are joined together at their lower ends by means of an integralbight portion 94 which may be secured to yoke 60 by any suitable means,such as by a rivet 96 extending through aligned openings in bightportion 94 of contacts 80 and 81 and bight portion 70 of yoke 60. Inorder to prevent any accidental electrical contact between either of theadjacent terminal screws 36 with the contact 80, the portion of barrier18 under opening 56 has been laterally enlarged between the terminals20, which enlarged portion extends upwardly to a plane beyond the upperedge of the terminal portions 22 and laterally spaced from each sidethereof. In order to permit the contact 80 to extend through body 2, anopening 98 is provided in the enlarged portion of the barrier 18 whichis of a size so as to closely receive the contact 89 therein. As shown,the arms 92 and 93 of contact 89 are spaced in opening 98, and opening98 is so formed that its side adjacent the center of body 2 engages theupwardly extending arm 93 of contact 8t so that arm 93 of contact 80 isrestrained from moving away from arm 92 when a grounding prong isinserted through opening 56. Also, if desired, the upper end of arms 92and 93 of contact 89 upwardly beyond the opening 98 may be bentangularly outwardly from each other to provide a flanged portion whichis engageable with the free end of an inserted grounding prong 130 so asto guide the free end of the grounding prong 130 properly between thearms 92 and 93. Accordingly, to provide clearance for the upper ends ofarms 92 and 93 in alignment with opening 56, the undersurface of cover40 in alignment with opening 56 is provided with an upwardly extendingrecess 3.

The method of making a grounded electrical connection by means of thegrounding prong 13d of an attachment cap 120 being inserted through theopening 56 is believed to be obvious. Such grounding prong 130 isinitially inserted through the opening 56 and forced downwardly so as toengage the flanges at the upper ends of arms 92 and 93 of contact 80.Inasmuch as the diameter of the grounding prong 130 is known, theopposed surfaces of arms 92 and 93, at their closest point, are spacedapart a distance somewhat less than the diameter of the insertedgrounding prong 130 so that upon such insertion the grounding prong 130forces the arm 92 of contact outwardly from the arm 93 thereof. Duringsuch bending of arm 92, the arm 93 is restrained by the inner surface ofopening 98 adjacent the center of housing 2 engaging arm 93. Withdrawalof the grounding prong 130 will obviously break the ground connectionand permit the arm 92 to spring toward arm 93 and extend angularlytoward the arm 93 of contact 80. Also, the spaced contact engagingprongs 111 of the attachment cap 130 will engage the blades 28 ofterminals 20 in somewhat the same manner to make and break theelectrical circuit between the outlet and the attachment cap 130 in amanner which is well known in the art. In general, the grounding prong130 extends outwardly from the attachment cap a distance somewhatgreater than that which the contact engaging prongs 111 extend. Ascontact 80 and blades 28 of terminals 20 all have their upper ends inapproximately the same plane, the grounding connection will be madefirst and broken last upon the insertion and removal of the groundingprong, respectively.

As can be appreciated, the insertion and withdrawal of the attachmentcap is often done in various ways which, as indicated, has caused damageto the cover 40. Accordingly, it will be noted that the projection 50 isprovided with an open-ended slot 100 which extends longitudinallyinwardly from the side of the projection 50 adjacent the projection 51above the straight side of the D-shaped opening 56. The lower side ofthe slot 100 is located outwardly of the outer surface 5 of cover 49 soas to form an outwardly extending projection 7 between the surface 5 andopening 56. In order to facilitate inserting a grounding prong 130, theportion of projection 7 adjacent opening 56 is provided with a surfacewhich extends angularly from the upper edge of projection 7 towardsopening 56. Also, if desired, the upper portion of the opening 56 andslot 100 may be provided with an angularly outwardly extending slope soas to guide an inserted grounding prong 139 during insertion. Thus, itwill be noted that a grounding prong may be inserted or withdrawn at anyangle with relation to opening 56 without causing any damage to thecover 40, as such prong will engage either the curved portion of theD-shaped opening 56, the sloping sides of the D-shapcd opening 56, orthe projection 7, all of which parts are of a size and have sufficientstructural strength to prevent fracturing thereof by a stress whichwould normally be placed thereon due to such insertion or withdrawal ofthe grounding prong 130, In particular, it will be noted that if agrounding prong 130 engages the projection 7 during the period it isbeing withdrawn, it may rock over the upper sloping surface ofprojection 7 to facilitate its withdrawal.

As indicated, projections 12 and 14 are laterally spaced from each otherso as to form a U-shaped opening at their end of body 2 in conjunctionwith the outer surface of end wall 10 in which the other contact 31,which is in alignment with opening 58, is located. As also described,one arm 68 of yoke 69 extends over the outer surface of each projection12 and 14 and therebetween so as to close the open side of the U-shapedopening and provide a rectangular opening for the contact 81 similar tothe opening 98 in which the contact 80 is located. Similarly, theundersurface of cover 46 adjacent the open ing 58 is provided with alongitudinally extending openended slot 9 to provide clearance for theangularly outwardly extending free ends of contact 81. Opening 58differs substantially from an opening 56 and comprises a longitudinallyextending elongated slot which is open at the adjacent outer end ofcover 40 adjacent the arm 68 of yoke 60 and extends above theprojections 12 and 14. The upper portion of opening 53 is provided withan angularly outwardly extending surface for the same purpose as thesimilar surface on opening 56. Further, it will be noted that theportion of the arm 68 of yoke 60- extending between the projections 12and 14 is provided with an integral inwardly and downwardly extendinglance 11, the free end of which is in engagement with the arm 93 of thecontact 81 so as to support the arm 93 from being deflected by theinsertion of the grounding prong. Lance 11 also supports the groundingprong during withdrawal in the same manner as projection 7. Theinsertion of the grounding prong 130 between the arms 92 and 93 ofcontact 81 may readily be accomplished by aligning the grounding prongwith the opening between the arms 92 and 93 of contact 81.

Referring to FIGS. 3 and 5, it will be noted that projection 14 of body2 is provided with an inwardly extending recess 15, of which only theouter end is shown and over which one end of the arm of an L-shapedconductor 17 extends so as to be substantially flush with the outersurface of base 4, and is provided with a slot, not shown, which extendsfrom recess 15 to slot 62, so that the other leg of conductor 17 mayextend therethrough and be connected to yoke 6i) by any suitable means.As shown, an opening is provided in the other arm of conductor 17 inalignment with the opening in the yoke through which rivet 96 extends,so that such rivet 96 may be utilized to secure the other arm of theconductor 17 as well as contact 81 to the yoke 60. A terminal screw 19is threadedly secured to the arm of conductor 17 located over the recess15 so that its shank portion, not shown, extends inwardly of the recess15, and so that a ground connection may readily be made to conductor 17,and consequently yoke 60, by placing the conductor between the head ofthe terminal screw 19 and the arm of conductor 17.

FIG. 4 illustrates another embodiment of my invention which is similarto the convenience outlet previously described, and accordingly, similarcomponents have been identified with the same reference numerals usedpreviously primed. As shown, an elongated cup-shaped body 2 is providedwhich is adapted to have its open side closed by an elongated cover 40'.The construction of this modification of my invention differs primarilyfrom that previously described in that an elongated yoke 60' is locatedbetween the cover 40 and body 2. Accordingly, the structure of body 2which is cooperable with yoke 60 as previously described has beeneliminated. The outer ends of yoke 63 and the general construction ofcover 40 and body 2' are however, similar to the cover 40 and body 2previously described. Body 2', cover 40 and yoke 60' are adapted to besecured together by suitable means such as a pair of longitudinallyspaced elongated bolts 21 which extend upwardly from the base of body 2through aligned openings in the body 2, yoke 60 and cover 40' and whichthreadedly engage the openings in cover 49'. Inasmuch as body 2', cover40' and yoke 60 are secured together by bolts 21, the central portion ofyoke 60' is provided with a threaded opening 23 in alignment with acentrally located opening 25 in cover so that a face plate may besecured to the outlet by means of a screw extending through opening 25and threadedly engaging the opening 23 in yoke 60'. Body 2 is alsoprovided with a recess 27 which extends laterally in body 2' inalignment with opening 25 in cover 40' and opening 23 in yoke 60' so asto provide clearance for such a face plate securing screw.

Cover 40' is provided with projections and 51' having openings 56' and58 which are substantially identical to projections 56 and 51, andopenings 56 and 58 previously described. Due to the difierent yoke 60' adifferent type of ground contact is required and certain modificationsof the body 2 and cover 40 have been made as a consequence of utilizinga diiferent type of grounding contact. As shown, yoke 60' is providedwith a longitudinally elongated opening 29 having a portion in alignmentwith opening 56' which is also in alignment with a laterally elongatedrecess 31 in body 2. An upwardly open U-shaped grounding contact 33 issecured to yoke 60' within opening 29 in any suitable manner so that onearm of the contact 33 is located adjacent one side of recess 31 and itsother arm is spaced outwardly from such one side of recess 31 so as tobe in alignment substantially with the adjacent side of the opening 56.Contact 33 may be so supported within opening 29 of yoke 60 by providingthe opening 29 with a pair of laterally inwardly extending projections41, only one of which is shown, at approximately the center of opening29. Contact 33 may then be secured to the yoke 60 by merely beinginserted through a portion of the opening 29 at one side of projection41 so that the arms of contact 33 are biased toward each other and sothat good electrical contact is established between the arms of contact33 and the yoke 66'. With such construction the inner arm of contact 33is located so as to be substantially in alignment with one edge of theopening 56 so that it may be engaged by an inserted grounding prong ofan attachment cap and deflected by such prong toward its other arm.Inasmuch as the inner arm of contact 33 may be deflected within body 2'and cover 40' it will be noted that cover 40 has been provided with arecess 3' similar to the recess 3 previously described. It isunnecessary however, to provide a recess 3 which extends on each side ofthe recess 31 and accordingly, it will be noted that the inner edge ofthe projection 7 is in alignment with the side of the recess 31 oppositefrom that which is engaged by contact 33. The function of the groundingcontact and the projection 7 with this construction is similar to thatpreviously described and accordingly, need not be repeated. If desired,the outer arm of contact 33 may be provided with an outwardly extendingarm 51 which extends over the upper surface of yoke 60' and which may bewelded to yoke 60 to insure that contact 33 is properly secured to yoke60'.

Yoke 60 is also provided with a laterally elongated opening 35 having atleast a part in alignment with opening 58' for the purpose of receivinganother grounding contact 33, as viewed in FIG. 8, at one end of opening35, in a manner similar to that in which a contact 33 is supported inthe opening 29. Body 2 is provided with a laterally elongated recess 37in alignment with opening 35 in yoke 60' to receive the lower portion ofsuch other grounding contact 33. It, of course, will be realized thatthe cover 40 must be provided with sufiicient clearance so that theother contact 33 supported in opening 35 may function as describedpreviously It is to be realized that yoke 60 can be provided with one ormore L-shaped conductor portions 17', similar to conductor 17 previouslydescribed, one arm of any one of which extends laterally outward fromyoke 60, as viewed in FIG. 8, and the other arm of which extendsdownwardly and is located in a suitable recess in body 21 so as to beaccessible externally of body 2.

It will be noted that the other end of yoke 60 adjacent opening 58 has aportion 43 which extends upwardly adjacent the lower portion of the openside of opening 53. Portion 43 of yoke 60' is provided with an inwardlyextending lance 11' which is generally similar to the lance 11previously described. Lance 11 extends angularly downward toward therecess 37 in body 2' and is located so as to have its free endapproximately in alignment with the outer wall 45 of recess 37. By thisconstruction, lance 11 directly engages the grounding prong 130 of anattachment cap when it is inserted or withdrawn to support the groundingprong during such operations similar to the manner in which projection'7, previously discussed, functions. Upon such insertion of thegrounding prong through opening 56 such other contact 33 supported inopening 35 will be engaged in the same manner as contact 33 supported inopening 29 is engaged as previously discussed.

Having described preferred embodiments of my invention, it is desiredthat the invention be not limited to the particular form specificallyillustrated and described herein as it will readily be apparent topersons skilled in the art that various changes and modifications may bemade in the particular structure shown without departing from the broadspirit and scope of the invention. Accordingly, it is desired that theforegoing be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. A wiring device comprising an insulating body having a pair of spacedwalls so as to define at least one opening therebetween, said bodyincluding an insulating cover located so as to extend over said opening,said cover having front and side surfaces and having a slot thereinextending therethrough and being open through one of said side surfaces,an elongated resilient electrical contact located in alignment with saidslot so as to be engageable by contact means inserted through said slot,one end of said contact being freely located adjacent the undersurfaceof said cover, a yoke member secured to said body having a portionthereof adjacent said one end of said contact, means on said portion ofsaid yoke extending into said slot toward said contact to limit movementof said one end of said contact theretoward, and means for securing saidbody and said contact in its aforedescribed relationship. r

2. A grounding electric outlet for receiving a plug having at least onecontact prong and a grounding prong, said outlet comprising a casing ofinsulating material including a hollow opensided base and a coversecured thereon, at least one electric contact and a grounding contactmounted in said base, openings in said cover aligned respectively withsaid contacts to permit access of said plug prongs to said contacts, oneof said openings being aligned with said grounding contact and havingone portion of its outer end extended laterally outward through a sideof said cover, and a yoke being secured to said casing and having aportion thereof located in said portion of said one opening to limit thedeflection of said grounding contact theretoward.

3. A wiring device comprising an elongated insulating base including apair of longitudinally spaced walls so as to define an openingtherebetween, an insulating cover being apertured for receiving powerblades of a plug and being located so as to extend over said baseopening between said spaced walls of said base and to form a housingtherewith, said cover having a portion thereof extending outwardlybeyond one of said base walls, a slot in said portion of said coverextending therethrough, said one base wall having a pair of laterallyspaced projections extending longitudinally outwardly therefrom so as tobe located adjacent the undersurface of said portion of said cover, saidslot in said cover being in alignment with a channel between saidprojections, a yoke member having a strap portion thereof extendingalong the side of said base opposite said cover and across said channelwhich is between said base projections, another portion of said yokeextending laterally of said strap portion and laterally of said baseadjacent the longitudinal limit of said base projections, an elongatedresilient grounding contact lo cated in said channel between saidprojections and having one end portion thereof secured to said strapportion of said yoke, said contact being in alignment with said coverslot so that at least said opposite end portion thereof is engageable bygrounding prong means inserted through said slot, means on said otherportion of said yoke for limiting lateral movement of said opposite endportion of said contact theretoward, and means for securing the parts ofsaid housing and said yoke together.

4. A wiring device comprising an elongated insulating base including apair of longitudinally spaced walls so as to define an openingtherebetween, an insulating cover being apertured for receiving powerblades of a plug and being located so as to extend over said baseopening between said spaced walls of said base and to form a housingtherewith, said cover having a portion thereof extending outwardlybeyond one of said base walls, a slot in said portion of said coverextending therethrough, said one base wall having a pair of laterallyspaced projections extending longitudinally outwardly therefrom so as tobe located adjacent the undersurfacg of said portion of said cover, saidslot in said cover being in alignment with a channel between saidprojections, a yoke member having a strap portion thereof extendingalong the side of said base opposite said cover and across said channelwhich is between said base projections, an elongated resilient groundingcontact located in said channel between said projections and having oneend portion thereof secured to said strap portion of said yoke, saidcontact being in alignment with said cover slot so that at least theopposite end portion thereof is engageable by grounding prong meansinserted through said slot, another portion of said yoke extendinglaterally of said strap portion and laterally of said base adjacent thelongitudinal limit of said base projections so as to retain saidgrounding contact within said channel against outward deflection in thebase longitudinal direction, and means for securing the parts of saidhousing and said yoke together.

5. A grounding electric outlet for receiving a plug having at least onecontact prong and a grounding prong, said outlet comprising a casing ofinsulating material, at least one electric contact and a groundingcontact mounted in said casing, a face side of said casing havingopenings extending therethrough in alignment with said contacts,respectively, to permit access of said plug prongs to said contacts, oneof said openings being aligned with said grounding contact and extendingoutwardly to face through another casing side which is generallytransverse to said face side, and a yoke being secured to said casingand having a portion thereof extending across the outer extent of saidone opening so as to define said one opening as an aperture ofpredetermined size for receipt of said grounding prong.

6. A grounding electric outlet for receiving a plug having at least onecontact prong and a grounding prong, said outlet comprising a casing ofinsulating material, at least one electric contact and a groundingcontact suitably located in said casing, a face side of said casinghaving openings extending therethrough in alignment with said contacts,respectively, to permit access of said plug prongs to said contacts, oneof said openings being aligned with said grounding contact and extendingoutwardly to face through another casing side which is generallytransverse to said face side, and a yoke being secured to said casingand having a portion thereof extending across an outer portion of saidone opening, and means extending inwardly from said one yoke portion soas to define said one opening as an aperture of predetermined size forreceipt of said grounding prong.

7. A grounding electric outlet for receiving a plug hav ing at least onecontact prong and a grounding prong, said outlet comprising a casing ofinsulating material, at least one electric contact and a groundingcontact mounted in said casing, a face side of said casing havingopenings extending therethrough in alignment with said contacts,respectively, to permit access of said plug prongs to said contacts, oneof said openings being aligned with said grounding contact and extendingoutwardly face through another casing side which is generally transverseto said face side, and a yoke being secured to said casing and having aportion thereof extending across an outer portion of said one opening soas to define said one opening as an aperture of predetermined size forreceipt of said grounding prong.

8. A wiring device comprising an elongated insulating housing having apair of longitudinally spaced laterally extending walls, said housinghaving its front side formed by a facing wall extending longitudinallybetween said laterally extending walls, said facing wall having aportion thereof extending longitudinally outwardly of one of saidlaterally extending walls, a slot extending through said facing wallportion, said one laterally extending wall having a pair of laterallyspaced projections extending 1; 1 longitudinally outwardly therefrom soas to be located inwardly of said facing wall portion, said facing wallportion slot being in alignment with a channel between said spacedprojections, a yoke member having a strap portion thereof extendingalong the side of said housing opposite said front housing side andacross said channel, an elongated resilient grounding contact located insaid channel and having one end portion thereof secured to said yokestrap portion, said contact being in alignment with said facing wallportion slot so that at least the opposite end portion thereof isengageable by grounding prong means inserted through said facing wallportion slot, another portion of said yoke extending laterally of saidyoke strap portion and laterally of said housing adjacent thelongitudinal limit of said spaced projections so as to retain saidcontact within said channel against outward deflection in the housinglongitudinal direction, and means for securing said yoke to saidhousing.

9. A wiring device comprising an elongated insulating housing having apair of longitudinally spaced laterally extending walls, said housinghaving its front side formed by a facing wall extending longitudinallybetween said laterally extending walls, said facing wall having aportion thereof extending longitudinally outwardly of one of saidlaterally extending walls, a slot extending through said facing wallportion, said one laterally extending wall having at least oneprojection extending longitudinally outwardly therefrom so as to belocated inwardly of said facing wall portion, a yoke member having astrap por- 12 tion thereof extending along the side of said housingopposite said front housing side, another portion of said yoke extendinglaterally of said yoke strap portion and laterally of said housingadjacent the longitudinal limit of said one projection, said facing wallportion slot being in alignment with a channel at least partiallydefined laterally by said one projection and said other yoke portion, anelongated resilient grounding contact located in said channel and havingone end portion thereof secured to said yoke strap portion, said contactbeing in alignment with said facing Wall portion slot so that at leastthe opposite end portion thereof is engageable by grounding prong meansinserted through said facing wall portion slot, said other yoke portionretaining said contact within said channel against outward deflection inat least the housing longitudinal direction, and means for securing saidyoke to said housing.

References Cited in the file of this patent UNITED STATES PATENTS1,927,245 Russell Sept. 19, 1933 2,051,856 Hubbell Aug. 25, 19362,420,103 Smith May 6', 1947 2,618,677 Parish, et al Nov. 18, 19522,664,552 Ericsson, et al Dec. 29, 1953 2,672,593 Shenton Mar. 16, 19542,682,646 Hubbell June 29, 1954 2,686,297 Hutt Aug. 10, 1954

